In factory automation (FA), production facilities placed in a factory are controlled by an industrial network system that includes various types of slave devices which collects data of and conducts control on the production facilities and a master device which conducts central control on these slave devices.
Technologies have been developed for an industrial Ethernet (registered trademark) to which the Ethernet technologies are applied, as one example of the industrial network system for use in the FA field. The industrial Ethernet, referred to also as a manufacturing industrial Ethernet, is a network that has introduced Ethernet technologies and apparatuses to the FA field in various layers. Various associations have openly disclosed the standards of the industrial Ethernet, one of which is Ethernet for Control Automation Technology (EtherCAT: registered trademark) promoted by the EtherCAT Technology Group (ETG).
When building this type of an industrial network system, first a design assistance device editor provided as personal computer software or a dedicated system is utilized to design a network configuration (namely, specification of a model, connection order, and addresses and various parameters assigned to the slave devices). Then, after the network configuration is fixed, based on its design information, various programs configured to operate in the master device are designed and developed and an actual network system (actual machine) is assembled.
In this case, the actual machine should preferably be assembled as designed. Actually, however, in a process where the actual machine is assembled, there are many cases where the configuration is changed due to addition of slave devices, shift in their connection order, and alteration of their addresses in order to solve problems and correct functions. Such changes in network configuration have an influence on developments of a master device program and, therefore, are desired to be reflected in the original design information as quickly as possible. Moreover, to minimize corrections in the program under development, changes and modifications of the design information should be reduced to a minimum. Conventionally, identification of portions to be changed and modification of the design information have all been performed manually and required a lot of manpower.
As technologies to present a network configuration to the user in a manner such that he can easily understand the network configuration, for example, those disclosed in Patent Documents 1 and 2 are known. Patent Document 1 proposes a mechanism that, if a new model of a PLC or slave device appears, a design assistance device reads an information file of the model such that models supported by an editor can be increased. Further, Patent Document 2 proposes not a technology about industrial networks but a method for providing GUI display of information of troubles occurring on the network along with the network configuration information.